In vivo confocal microscopy of a family with Schnyder crystalline corneal dystrophy

Objective: To analyze corneal morphology in Schnyder crystalline corneal dy strophy (SCCD) in vivo. Design: Observational case series. Participants: Five eyes of four patients of various belonging to the same f amily were examined. Methods: The eyes were examined using in vivo confocal microscopy (CM), Main Outcome Measures: The corneal morphology including keratocytes and str omal extracellular matrix, as well as basal epithelial/subepithelial nerves is, described. Results: The right eye of a 48-year-old male patient had been treated with anterior keratectomy and the left eye with phototherapeutic keratectomy (PT K), The right eye presented with increased stromal reflectivity owing to ac cumulation of extracellular matrix and large subepithelial crystalline depo sits. Far fewer crystals could be observed in the left eye. The haze, howev er, was increased, either because of the dystrophy or the excimer laser tre atment. The anterior keratocytes appeared irregular, and the subepithelial nerves were undetectable in both eyes. His 78-year-old mother showed more a dvanced changes with dense crystals, highly fibrotic stroma, and severely d amaged corneal innervation. The partly irregular anterior keratocytes of th e 9- and 7-year-old children contained intracellular deposits, although the corneas were clinically clear with only subtle subepithelial crystalline f ormation. Accumulation of similar reflective material was also observed in association with the prominent subepithelial nerves, Conclusions: In the early stages of SCCD, highly reflective deposits accumu late intracellularly and around anterior keratocytes and along subepithelia l nerves. With time, the normal corneal architecture becomes disturbed by l arge extracellular crystalline deposits and accumulation of highly reflecti ve extracellular matrix resulting in central opacity and disruption of the subepithelial nerve plexus. Furthermore, neural regeneration after keratect omy appears delayed in SCCD.